A 1.7 Å resolution co-crystal structure of U7BR from Schizosaccharomyces pombe in complex with Ubc7 is reported. Structural comparisons and biochemistry suggest that U7BR presents a steric impediment to E1 binding and inhibits E1-mediated charging, respectively.

Summary Post-translational protein modification by ubiquitin (Ub) and ubiquitin-like (Ubl) proteins such as small ubiquitin like modifier (SUMO) regulates processes including protein homeostasis, the DNA damage response, and the cell cycle. Proliferating cell nuclear an...

Nuclear RNA exosomes catalyze a range of RNA processing and decay activities that are coordinated in part by cofactors, including Mpp6, Rrp47, and the Mtr4 RNA helicase. Mpp6 interacts with the nine-subunit exosome core, while Rrp47 stabilizes the exoribonuclease Rrp6 a...

Significance Posttranslational protein modification by ubiquitin (Ub) regulates aspects of biology, including protein turnover and the cell cycle. Proteins and enzymes that promote Ub conjugation are therapeutic targets because they are sometimes dysregulated in cancer,...